686865100 has 72 divisors (see below), whose sum is σ = 1570399488. Its totient is φ = 260251200.

The previous prime is 686865043. The next prime is 686865121. The reversal of 686865100 is 1568686.

It is a happy number.

686865100 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 244705 + ... + 247495.

It is an arithmetic number, because the mean of its divisors is an integer number (21811104).

Almost surely, 2^686865100 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686865100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (785199744).

686865100 is an abundant number, since it is smaller than the sum of its proper divisors (883534388).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

686865100 is a wasteful number, since it uses less digits than its factorization.

686865100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2935 (or 2928 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 686865100 is about 26208.1113398123. Note that the first 3 decimals coincide. The cubic root of 686865100 is about 882.3153131056.

The spelling of 686865100 in words is "six hundred eighty-six million, eight hundred sixty-five thousand, one hundred".